Zero Liquid Discharge
Zero Liquid Discharge and Minimal Liquid Discharge.
Reducing Wastewater. Protecting Water Supplies.
Kiewit helps clients protect water resources and meet stringent discharge regulations with cutting-edge Zero Liquid Discharge (ZLD) and Minimal Liquid Discharge (MLD) technologies that can minimize or eliminate wastewater discharge while maximizing water recovery.
Our teams specialize in designing and building complete ZLD and MLD systems for industries looking to implement advanced water recovery and wastewater management practices.
Understanding ZLD & MLD Technologies
As industries place greater stress on water resources through increasing demand and with increased regulation on total dissolved solids (TDS) concentration, advanced treatment solutions become essential for sustainable operations.
ZLD
Eliminates liquid discharge entirely through mechanical or atmospheric systems. While highly effective, it can involve complex, energy‑intensive evaporation systems or require extensive land for evaporation ponds. Kiewit’s expert understanding of chemistry, metallurgy and operation of these systems is critical to long-term operation and design life.
MLD
Reduces the volume entering the ZLD system by maximizing water recovery through advanced treatment techniques, helping to minimize the size, capital cost and operations cost of ZLD implementation.
How ZLD & MLD Systems Work
Reverse Osmosis (RO) serves as the backbone for both MLD and ZLD systems, separating clean permeate from concentrated brine. But excellent RO performance often includes multiple pretreatment processes. These processes often include:
Biological Treatment
Removes organics and ammonia from the wastewater stream, preparing it for advanced treatment processes.
Softening Process
Eliminates hardness, and potentially silica, from the water, which can improve recoveries and minimize scaling.
Ion Exchange
Provides final polishing to ensure adequate pretreatment for RO to ensure optimal performance.
Advanced RO Configurations
Multiple RO configurations can be used to optimize recovery rates based on feedwater quality and site-specific goals. These configurations include, amongst others:
- Osmotically assisted RO or low salt rejection RO
- Batch and semi batch RO
- High pH RO
- Ultra-high-pressure RO
Kiewit and ZLD
Kiewit is ready to help all industries design and build complete MLD and ZLD systems to efficiently manage their water and wastewater needs while protecting valuable water resources and minimizing their environmental impacts.
Ready to Implement Zero Liquid Discharge?
Connect with our team about engineering and construction support on your next water infrastructure project.
For vendor or supplier partnerships and all other inquiries, please visit our contact us page.